For unicyclists whose legs are paralyzed?
Len Mel, that thing looks cool, I would love to see it in action!
Yeah, any chance of a vid?
Well since I sold my take down 36" wheel I have breathed some new life into my 700X (project 32) by re-building the wheel around my schlumpf with the adaptors LanceB was nice enough to send me. I really like it in high gear, it feels so natural with the 137mm cranks.
I would like to make a new narrow tire again and try it out with 127s. The 700X feels much more natural geared up compared to the 36" wheel that I had very briefly. Itās just so much lighter!
Stay tuned folks, there should be BIG things in the works this summer.
I call this my Frankenwheel. Itās my first prototype and I can already see a number of changes Iāll be making on my next frame once I finish this one and test it out.
Iāve used a variety of bike parts in order to accomplish what I want to end up with and so far so good.
My goal is to have a multi-geared 26 uni that is built for speed. I wanted a frame that is designed around a disc brake bike hub with 6 speeds (with the option to add/remove more gears). I keep hearing that a derailleur is a flop on a unicycle. However over the last 20 years Iāve heard a lot of criticism of certain things in the biking world regarding new technology and inventions that wonāt work but in the end they did work and became part of the norm. So I am here to see for myself if it will work or not.
As for the freewheel and the disc brake, Iāve been riding unicycles forever and I can pull manual on a mtn bike and just cruise on it for some pretty lengthy distances so Iām confident that I can apply these same techniques on my Frankenwheel once itās done. I know it will be a challenge to master my gizmo but I think that the challenge is whatās going to make it fun.
The shifters will be attached under my seat and Iāll just hold onto the brake with my right hand to aid in balance.
I have seen a lot of talented DYI builders on this site and some of my ideas have come from them, other ideas have come from my desire to build something different from the love of the activity of riding one wheel.
The first pic is what I have completed so far. All I need now to finish it is the correct size tubing for the seat tube and get it welded on. For the second pic, I just taped a seatpost and seat to give you a better idea of what the finished product will look like. But the finished product will have the seat tube mounted in the middle of the bridge, not behind it. The 3rd pic is the mechanical mess of my Frankenwheel.
The pics came out a bit hazy but you get the idea
Woody
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Nice
That thing is one part HuniRex, one part Red Menace, two parts bike, and 100% awesome.
Once question, did you consider having the cranks attach to a spindle going through a bike hub like the other jackshaft designs? I would think that that would be stronger and simpler.
The reason people scoff at derailleur systems on unicycles is that we are stuck on the idea of having āfixedā wheels. People experimenting with freewheel unicycles is slowly changing this, there is no reason not to use a derailleur if you also have a freewheel.
The seatpost is probably fine inline with the rest of the frame as you have planned but if the aesthetic of nice clean lines isnāt that important you may want to shift the saddle forward rotating all those moving bits away from the riders knees.
Ok, itās not the same scale as the DIY-Rex above, but still unicycle related. Itās my attempt at copper wire jewelry.
Iām going to tarnish it with some heat & throw it in the rock tumbler for a few days.
Very nice. I would only suggest to make the ends in different length:
Hey thanks, Eric
Iāve been lurking on and off this site for awhile now but Iām not too familiar with a lot of the current names of some of the unicycles mention here. I had to look up the Hunirex and the Red Menace to know what you were referring to but I am aware of both designs.
I can see the similarities between the Hunirex and my Frankenwheel regarding the split bottom bracket. However, I have to say that the Hunirex has a much nicer version of it. I have no idea how itās constructed but on mine I had to use 2 different bottom brackets and modify them to get what I wanted. I havenāt been able to test the durability of my BB yet but so far it feels solid. Ironically enough, I planned to go with the split version long before I ever saw the Hunirex because I just couldnāt figure out a way to use a freewheel with a disc and still be able to pedal. At one point I was thinking about modifying a thru axle rear bike hub that would allow me to attach cranks to it, and for kicks I might still try that method just to see if it can work. Another reason I went with this design is to have a lower center of gravity to aid in the coasting aspect, but it looks like the Hunirex had me beat on that issue too.
As far as the jackshaft designs go, I didnāt even know they existed until recently. Had I known, I would have gone that route instead of going thru all the experimentation, cost, and parts Iāve used.
Thanks for the support with my decision to go with a derailleur system. I was actually expecting some criticism for it due to some of the articles I came across. But I have to say that it feels solid and shifts exactly the way I want it toā¦ smooth and accurate. But again, I havenāt been able to give it a real world test experience yet so it could end up being a flop. If it flops, then Iāll drop the derailleur and adjust the leading gears, like the Hunirex. Oh one big difference between my Frankenwheel and the Hunirex, I have zero chain slop due to the adjustable chain tensioners.
The Red Menace is such a great idea and such a clean looking design. Like Unisk8er, I never drew up any plans for mine. I just experimented and eventually built up what I had in mind. After building the Frankenwheel prototype and pondering about all the pros and cons of what I did and what I have ended up with I can say that the next two designs will be more thought out and will most likely have some paperwork to support the builds.
As for all those āmoving bitsā, they will be behind me not in front. I should have mentioned that. The derailleur leads the front.
Woody
Thanks Ernst,
The picture doesnāt show it well but the pedals are level and from the centre - like hands at 9 & 3 on the clock. It seems the simplest & most natural. I tried to hammer the them flat like pedals but in the end I didnāt like the way it looked so I left them cut & filed.
I got to ride the Huni Rex in England recently and itās quite interesting. It feels surprisingly good considering the pedals are so low that you canāt really lean much in the turn without striking the ground. Long cranks not possible. The frame is very nicely made but there were some production problems (fixed) in the first version. UDC UK is selling them cheap and theyāre going pretty fast. I have a lot of experience riding geared up so it didnāt take long at all to get used to. It is funny riding fast so low to the ground.
I wanted to chime in to say that I think this is a really interesting design. Great work! What I like about it is the fact that you can use a regular bike hub. Iām also intrigued about the lower pedal position and whether or not it would make coasting easier like it does on a BC wheel with drop plates vs. pegs. I am no engineer. In fact, I pop tubes changing tires and have tools break in my hand regularly. Not long ago I spent 10 minutes trying to get a crank off with the bolt still on. And Iāve removed cranks dozens of times! What I do have is nearly a yearās experience riding freewheel unicycles. Since January Iāve ridden nearly 700 miles on my different freewheels. Like Eric I have some concern about the chain rubbing or pinching your legs. On most of my unicycles Iāve rubbed the paint right off. There is a tendency to brace your leg against the frame on a freewheel unicycle, especially when first learning or when extra leverage is needed (like going down a very steep section). However, itās easier to keep your legs away from the frame when pedaling and when not pedaling the chain shouldnāt be moving. It may be that something like KH Percussion leg armor is enough protection. My other big concern is the safety of the sprocket and chain during a UPD. You may already have something planned but some kind of bumper is essential. Except when I hit a bump and fall forward, most of my UPDs push the saddle backwards, often quite violently. Please keep us updated on your progress! And bring your invention to Unicon if youāre going! If you havenāt seen this write up by Bruce before (which includes a great video) you may want to check it out:
Waaalrus, hey first off, I have to admit you are the King of coasting. I have seen your vids on utube and all I can say is wow! I donāt see myself being that graceful and coasting the distances youāve posted but I hope to be close to it. You have it down, brother. Youāre an inspiration to those of us who want to go the freewheel route.
Thanks for the compliment on my build. I finally got the seat tube welded into the frame and I am expecting the seat and seatpost sometime this week. So hopefully Iāll get the chance to test the Frankenwheel out.
You made a great point about adding some type of bumper to protect the cogs. When I first added the cogs, the frame tipped backwards and snapped one of the cogs in two. Apparently they canāt handle any type of side load or impact for that matter. Hardened nickelā¦ hum, I should have gone with chromo cogs instead. And after watching some of your vids that included some of your wrecks I agree that I need to protect the gearing system as much as possible. Iām currently working on a convenient way to add some type of protection and I have a few ideas rolling around in my head. But any input or ideas you or anyone else has, please share your thoughts.
Another great point you made is how you press your legs up against the frame when youāre coasting. Now I get the point about the chains. The last thing I want is to have the hair on my legs ripped out like Iām using an oldschool epilady.
I wonāt be going to unicon but I will keep you guys posted on my build and progress. Thanks again for the positive input. Keep posting the coasting vids.
Woody
Feels like I received too much spam starting with āEnlargeā ! 
I received this beauty yesterday and just managed a global pic and a width check (82mm all right with 25mm diameter cut-outs).
Still have to weight it to confirms how close is the manufacturerās announced weight (850g) from reality.
Stay tuned 
Wow, that rim is fat! I was looking into Surly rims for my fatty muni project, but that looks much better. If only it came in 29".
For what I know, in 29" the biggest available is the Surly Rabbit Hole rim (50mm) which is barely wider than a KH rim.
There isnāt any oversized tire in 29". The biggest available is the Surly Knard 29x3.0 and it is plenty big already =)
Unicycle buy advice
Hey guys 
I donāt know if I should post here (Iām new to the forum), but this deal got my interest: http://imgur.com/a/cq4xq#0
Itās 2nd hand, with a 20ā wheel and a flat airchamber. Heās asking 35ā¬ and throwing in an air pump. Now, my questions are:
- Does it look good for a beginner and for the price (35ā¬)?
- What else should I ask /by mail) or look for if I arrange to meet him?
- Getting a new air chamber at a bike shop would be rather easy and not too costly, right?
sorry if I hijacked the thread
It looks like a reasonable beginnerās unicycle at a reasonable price.
Are the crank arms fixed tightly onto the axles? There should be no movement at all there. Does the wheel turn easily and freely, and without making any squeaks or scrapes or other noises? Does the seatpost clamp hold tightly enough that the seat doesnāt twist to another direction when you drop the unicycle? (You will drop it a lot.)
Yes, easy and not costly. It should also be easy to find one in stores that sell sporting equipment, or bicycles and tricycles as toys for children.
Youāll also find tire pumps like the one thatās included, at around the same price as the inner tube! Having said that, I use one just like it all the time.
Good luck, and let us know how your unicycling progresses if you get it.
Nice wheel, but I have a question:
That large spoke offset in the rim, doesnāt that make the wheel very flexy in sideways direction?
Looking in riding direction, shouldnāt there be a triangular shape in the spokes, from left flange, to rim, to right flange, to make it stiff, sideways? With this offset in the rim, it is more looking like parallellogram. Triangular constructions are stiffer than parallograms.
I see this more often in these wide rims, can anyone tell me why?